Ask HN: Why Game In Browser

In the past few days I have noticed an increase in the mention of "html5 games" in my daily Internet browsing. This led to ask a question I don't think anyone has yet to answer. Why game in browser ? The consoles all have great games and so does the PC. Why is everyone so fascinated by a game in browser when all these better looking and more complex games exist. A coolness factor I can understand but not much else.